Mystery Damp in Wall Damp can be a major issue in the home. Find answers to questions or post your own here.

[LSSmith]

Live in an end terrace and have had continual damp problems with the exposed side wall (which connects to next doors single story extension).

Had orange damp marks showing by the floor of the first floor wall and by the ceiling of the ground floor wall directly below it. Had outside checked and supposedly re-pointed but damp still coming in. There was actualy water coming in initially which has now stopped and seemed to have cleared up after the walls were pointed but now the wall is sticky so assume this is still damp coming in?

Next doors flat roof seems fine and there is no pipework which could create this problem.
Can you please help - at the end of my tether!

:cry:[/quote]

[matchmade]

Sorry, I can't visualise this - surely you mean the rear wall connects to your neighbour?

Any chance it's an *internal* problem, like a leaky pipe from your neighbour's bathroom? You say no, but the first-floor problem is very unusual. And ae you positive the flat roof is OK? It may look OK on surface inspection but actually be cracked and letting water through. How about asking your neighbuor to add flashing in the corner where his or her flat roof meets your wall?

Final option - get a builder or surveyor in for another opinion. Don't try to do it all yourself.

I suspect the flat roof, in which case you will have th tricky of persuading your neighbour to re-do it. How old is it? More than 10 -years - quite possibly a leak. That's why you need a professional to provide supporting evidence.

[LSSmith]

Thanks. Sounds like its going to be a bit of a nightmre - building next door is actually Jehovas Witness church. Wish me luck!

[matchmade]

If it's any consolation, whatever's happening to you in that corner is almost certainly affecting them as well, so they may actually be grateful to you for pointing it out.

Well, you never know!

I had a somewhat similar situation in a semi-detached house I bought - damaged pointing on ridge tiles, on my neighbour's side. The water was running through into my space internally but not his, but it was causing damp and rot on his roof timbers, though luckily we caught it in time. It can be hard work persuading people that there's a real problem if it involves them spending any money, which is why evidence of damage on their side and if necessary a third-party report is crucial, not so much in establishing blame as saying "we have a joint problem here".

Good luck.

[Big Steve In Brid]

I am new to this site. Spent a while reading thru' varios probs, and spotted this one.
I have been "doing up" my house, which was buit in 1902, as a B&B for the last six years. Most of the work other than PVC windows and the roof have been done by myself.
I too had this mysterious damp problem in one of my top floor rooms. As all the roof and guttering is new it took me a while to find the prob. The internal walls at the front of my building are lath and plaster. What I found was the plaster behind the laths had loosened and broken off, fallen down and started backing up from about floor level. As the gap between int and ext walls is only 30'ish mm, the cavity was breeched and moisture had crossed over from the external brick, thereby causing damp.
The solution, knock off all the old plaster. Remove 3 or 4 laths from floor level. Clear out all the debris. Over-board with foiled plasterboard and skim.